diff --git a/core/restservices.class.inc.php b/core/restservices.class.inc.php
index 518e8a8cd..b2b519401 100644
--- a/core/restservices.class.inc.php
+++ b/core/restservices.class.inc.php
@@ -135,8 +135,15 @@ class ObjectResult
  */
 class RestResultWithObjects extends RestResult
 {
+	/** @var DBObject[] */
 	public $objects;
 
+	public function __construct()
+	{
+		parent::__construct();
+		$this->objects = array();
+	}
+
 	/**
 	 * Report the given object
 	 * 	 
@@ -185,6 +192,7 @@ class RestResultWithObjects extends RestResult
 
 class RestResultWithRelations extends RestResultWithObjects
 {
+	/** @var array */
 	public $relations;
 	
 	public function __construct()